Along an assembly line, various types of articles, such as diapers and other absorbent articles, may be assembled by adding components to and/or otherwise modifying an advancing, continuous web of material. In some processes, advancing webs of material are combined with other advancing webs of material. In other processes, individual components created from advancing webs of material are combined with advancing webs of material, which in turn, are then combined with other advancing webs of material. In some cases, individual components created from advancing web(s) are combined with other individual components created from other advancing web(s). Webs of material and component parts used to manufacture diapers may include: backsheets, topsheets, leg cuffs, waistbands, absorbent core components, front and/or back ears, fastening components, and various types of elastic webs and components such as leg elastics, barrier leg cuff elastics, stretch side panels, and waist elastics. Once the desired component parts are assembled, the advancing web(s) and component parts are subjected to a final knife cut to separate the web(s) into discrete diapers or other absorbent articles.
In some instances, contraction around the waist of a wearer may improve the perceived fit of the absorbent article on the wearer. In some processes, discrete lengths of layered elastic substrates, such as waistbands, are bonded to absorbent articles to improve the perceived fit of the absorbent article. The waistbands may include an elastic material bonded to one or more layers of nonwoven substrate. The elastic material may include elastic films, ribbons, and/or strands. In some processes, the waistband may be formed by joining the nonwoven substrate with a plurality of elastic strands. In some processes, the elastic strands are stretched at full strain and joined to the nonwoven substrate. As a result, when the waistband is allowed to relax, gathers form in the waistband and the basis weight of the waistband increases such as shown in FIG. 1A. However, when the absorbent article is fully stretched, such as during application of the absorbent article to the wearer, the waistbands fully extend and flatten around the waist area as shown in FIG. 1B. As described more fully hereinafter, the basis weight of the waistband may also decrease. As a result, the flat, low basis weight waistband may negatively affect the real and/or perceived fit of the absorbent article. Therefore, it would be beneficial to have a method and apparatus for bonding a waistband to an absorbent article that is stretched below full strain such that the waistband continues to have gathers when the absorbent article is fully stretched.